CA2059260A1

CA2059260A1 - Hoodliner

Info

Publication number: CA2059260A1
Application number: CA002059260A
Authority: CA
Inventors: Melvin Ivy Todd
Original assignee: Individual
Current assignee: Chicopee LLC
Priority date: 1991-01-15
Filing date: 1992-01-13
Publication date: 1992-07-16
Also published as: US5164254A

Abstract

HOODLINER

Abstract A composite material is provided for use in a vacuum thermoforming process, which material is easily handled and presents an aesthetically pleasing fabric-like surface. The composite material comprises an outer layer of nonwoven fabric comprising thermoplastic fibers capable of elongation upon the application of heat and tensile force so as to be readily conformable to shaping in the vacuum thermoforming process. The composite material further comprises an inner layer of thermoplastic film.

Description

2r~

HOODLINER

Background of the Inven~ion This invention relates to the field of vacuum thermoforming and in particular relates to materials and processes for providing a finished product having a fabric-like surface as well as the thermoformed articles employing such materials.
Vacuum thermoforming has perhaps found its greatest application in the field of packaging wherein items have been protected by closely fitting packaging which conforms to the shape of even irregular items. In some such processes, often referred to as ~skin packaging~, the item i3 placed on a cardboard backing. A thermoplastic material such as a film of polyester, polyvinylidene chloride, polyvinyl chloride, polyvinyl acetate, polyethylene or polypropylene is laid over the item and is heated and then drawn down onto the item using vacuum.
The film, owing to its thermal plasticity, will conform to the shape of the item and, in the plastic state, will adhere to the cardboard backing and remain so adhered after cooling, thus encapsulating the item between the film and the backing. In the so-called ~blister packaging~ application, the film is heated and vacuum formed by being drawn into a mold designed to produce a film shaped to accommodate the item to be packaged. The item is t~en placed into the so-shaped film, often while still in the mold, and a cardboard backing is then adhered to encapsulate the item.

It has been discovered that a particularly useful applicatio~ of vacuum thermoforming is in the field of liners such as hoodliners, trunkliners, and roof liners ~s~

(i.e., headliners) for inner surfaces of vehicles . These l~ners comprise ~ re~a~ivel~ thick body of J~oise a.,dior heat insulating material such as, for e~ample, fiberglass. The body is molded to fit the contours of the inner surface of automobile hoods, trunks and roofs and as such, the body comprises an irregular shape whose surfaces are interrupted by protrusions and depressions.

While the fiberglass body provides e~cellent insulation properties, both for aesthetic and practical purposes, the nature of thi~ material presents drawbacks. Firstly, the fiberglass insulation tends to be brittle, causing breaking of fiber and formation of particles which are disadvantageous both during the liner installation process and in use. Secondly, the surface tends to be rough and aesthetically displeasing.

Accordingly, there ha~e -been several suggestions for applying to this insulation surface a material which protects against such breakage and is more aesthetically pleasing. Such suggestions are to be found, for e~ample, in U.S. Patent 3,263,530 to A. Marzocchi et al. wherein a fiberglass headliner is provided with a laminate cover comprising layers of thermoplastic film sandwiching a glass fiber cloth and adhered by means of heat and compression. Further, in U.S. Patent 4,002,367 there is , described a nonwoven cover adhered to the fiberglass body of a liner by employing an adhesive. Further still in U.S. Patent 3,620,906 to Harmes wherein a polyethylene layer and a fiber layer are laminated to the fiberglass body.

While each of these suggestions have to an e$tent, improved the installation and use problems associated with the fiberglass insulation liners, they each suffer from 2~

drawbac~s. In some instances the prior suaaestions result .n a Pl~s -c l ke ol!~er surface which i~ ~isible in the finished vehicle and aesthetically displeasing. In other instances, the prior suggestions result in a requirement S for the installer to handle several different layers of material and, in certain circumstances, handle relatively weak, easily torn, easily creased, nonwoven materials.

Accordingly, there is a need for a material which can be combined with an insulating body such as a fiberglass body, which can have an irregular surface, which can be handled and installed without e~traordinary care, and which will present an aesthetically pleasing surface.

Summary of the Invention A composite material is provided for use in a vacuum thermoforming process, which material is easily handled and presents a~ aesthetically pleasing fabric-like surface. The composite material comprises an outer layer of nonwoven fabric comprising thermoplastic fibers capable of elongation upon the application of heat and tensile force so as to be readily conformable to shaping in the vacuum thermoforming process. The composite material further comprises an inner layer of thermoplastic film.

In accordance with the teachings herein, at the interface between the layers, the film impregnates into the fabric to a degree such that the combined thickness of the nonimpregnating portion of the film and the impregnated portion of the fabric is greater than the thickness of the portion of the fabric not impregnated with said film.

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, .

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It has been discovered that when this com~ ma~eria is provided in a vacuilm thermo-co~ming r~oce~ wher~ d vacuum is drawn on the inneL layer's surface ~i.e., a lower pressure is irduced on the surface of the inner layer then on the surface of the outer layer) while said material is in the heated state, the impregnating portion of the film will be drawn away from the outer surface of the outer layer, thus e~posing fiber in the area of the outer surface and providing a more fabric-like appearance. Accordingly, by employing the composite material of this invention in a vacuum forming process, such material will have the benefit of the convenience of handling a material which behaves essentially as an all plastic film material. After thermoforming, such material will exhibit the aesthetic properties of a fabric.

Brief DescriptiQn of the Drawin~s The invention will be described in more detail in the following description, taken together with reference to the accompanying drawings wherein: `

FIG. 1 is a schematic front elevational view of a manufacturing line for manufacturing an embodiment of the composite material of this invention employing the processes taught herein;

FIG. 2 is a perspective view of an embodiment of the composite material of this invention;
FIG. 3 is a photomicrograph o the composite material illustrate~ .n ~IG. 2 prior to being employed in a vacuum thermoforming process;

FIG. 4 is a photomicrograph of the composite material illustrated in FTC- 2 ar~er having beer sub~ected ~.o a vacuum thermoforming process;

FIG. 5 is a schematic, partial, longitudinal~
cross-sectional view of an embodiment of the composite material of this invention in the process of being vacuum thermoformed about a portion of a hoodliner; and FIG. 6 is a schematic, partial, longitudinal, cross-sectional view of the embodiment of the composite material of this invention in a further step in the process of ~acuum thermoforming following that illustrated in FIG. 5.
Detailed Description of the Invention_ Referring now first to FIG. 1, illustrated therein is a schematic, front, elevational view of a manufacturing line for producing the emhodiment of the composite material 10 of this inven~ion, illustrated in FIGS. 2 and 3, with the machine direction illustrated as right to left.

Nonwoven fabric 12 is introduced from a supply source (not shown~ and passed between idle roll 14 and heated roll 16. The nonwoven fabric should be a stabilized web of fibers having, preferably, thermoplastic properties (i.e.
the ability to elongate under influence of the heat and stress encountered during a vacuum thermoforming process~
so as to be capable of elongation upon the application of heat and tensile forces in order to facilitate conformance with the body to which the fî~îsned composite material is to be vacuum thermoformed and adhered to. Preferably, such fibers should have a length which range from about 19 mm to about 50 mm and still more preferably from about C~IC-758 5~

25 mm to about 40 mm. The deni~r of the fibers may range fr~ about 1 t-o about 6 and pre~Qrahl,~ from a~nllt 1 1~ ~o abGut 3. The fibers should have an elongation of at least about 10% and preferably, at least about 20% as measured by the method of ASTM D2101-90. Usable fibers include those o~ nylon, polyester, polyethylene, polypropylene, or even the so-called thermoplastic bicomponent fibers as are described in U.S. Patent No. 3,381,074.

The web of fibers forming the nonwoven fabric 12 may be laid down by any of several methods taught in the art such as for e~ample, the so-called dual rotor webber described in U.S. Patent No. 4,018,646, or the transverse webber described in U.S. Patent ~o. 4,927,685. Such laid down webs may then be stabilized by various methods already known in the art such as by adhesive or thermoplastic bonding, or by fluid or mechanical entangling or combinations thereof. A preferred stabilized nonwoven fabric is that produced by the methods taught in U.S.
20 Patent No. 3,485,706, the so-called hydroentanqling or spunlaced process.

The stabilized fabric should range in weight from about 0.5 to about 2 oz/sq. yd. and have a thickness o~ about 10 to about 20 mils and preferably from about 15 mils to about 18 mils. Within these ranges, the choice of weight and thickness will be chosen to suit a particular purpose;
however, to produce a composite material useful for laminating to the insulating materials for vehicles as described herein, it is preferable that the weight ranges between about 1 to about 1.5 oz./sq. yd. and that the thickness range between about 15 to about 18 mil~.
Adherence to these prescribed ranges will result in a material having the proper impregnation of the fabric prior to the thermoforming process, and being capable of r~a~

havi~g the impregnating ilm recede aw~Y from t~e f~hric advantageously in the a~plic~tior co vehicl~ l~ne.s.
Additives may ~e emp~oyed in the stabilizer fabric such as binder, to mor~ substantially stabilize the fabric, and pigments, to provide the fabric with color. As has been described in the aforementioned prior art, laminates of insulation and cover materials should be color matched for aesthetic reasons.

Referring again to FIG. 1, the fabric 12 is passed around heated roll 16 and is preferably preheated to a temperature of between about 170F and about 212F, and more preferably to about 180F to about 190F. As the fabric 12 is passed around the heated roll 16 and preheated, a film 18 is e~truded from a flat film die 20 by means of an estruder 22. The film 18 is deposited onto the preheated fabric 12 at a short distance from the esiting of the flat film die while the film is still in the molten state. The choice of thermoplastic polymers or combinations of polymers selected for the film will, of course, vary depending on such factors as the ultimate employment of the composite material, the na~ure of the fabric with which it is to be combined, the relative thickness of the desired films, the seal temperatures and perhaps the nature of any material onto which the composite material is to be vacuum thermoformed. Such polymers as polyester, polyvinylidene chloride, polyvinyl chloride, polyvinyl acetate, polyethylene or polypropylene are all useful in certain circumstances. Pr~ferably, polymers having melt temperatures in the range of from about 230F to about 425F are useful.

In the circumstance wherein the composite material is to be sealed to itself~ as will be described further herein, minimum seal temperature is also a factor in the selection C~IC-758 ~5~V

of a suitable material. In general, such minimum seal temperatllres ~hould range betwee}l ~bou~ ~5~'F to ab^ut 375F and preferably from about 275F to about 325F. A
polymer of choice, in particular for use as a composite material for thermoforming onto Yehicle liner ;nsulating materials, is linear low density polyethylene film. This polymer is applied to the fabric at film thickness of from about 3 to about 9 mils and preferably 3 to 7 mils.

Referring again to FIG. 1, the combined film and fabric are ne~t passed into the nip between heated steel roll 16 and a resilient roll 24. The application of heat and pressure at the nip serves to cause the molten thermoplastic polymer of the film 18 to impregnate the adjacent portions of the nonwoven fabric 12, as is illustrated in FIGS. 2 and 3 and described hereinafter~
This impregnation is advantageously carried out in the process e~emplified herein by use of the heated steel roll 16 to pre-heat the nonwoven fabric and additionally to maintain a high temperature within the nip. Mip pressure is maintained by use of the resilient roll 24 operating in cooperation with the steel roll 16 to produce nip pressures of between about 20 to about 90 pounds per linear inch. In a preferred embodiment of this invention the temperature of the steel roll 16 is maintained at from about 190F to about 205F, the temperature of the resilient roll 24 is maintained at from about S5F to about 75F and the nip pressure is maintained at about 40 to about 60 pounds per linear inch. The line speed may range from between 30 to about 300 feet per minute.

It will be understood Dy one skilled in the art that the parameters set out herein with respect to temperatures, pressures and line speed may all be controlled so that with a given film and fabric, various degrees of 2~5~

impregnation are attainable ~nd~ in the e~tre~e, may s~lt in ~ full~ impreg~at~d ra~ric or ;~stead~ a fa~ric impregnated only at the interface of the film and the fabric layers. Preferably, for most thermoforming processes, the minimum degree of penetration should be about 25% and, more preferably, about 30%; wherein such percentage is the percent of the total thickness of the fabric impregnated with the film polymer.

The composite material passing from the nip between rolls 16 and 24 nest pass around resilient roll 24 and then between roll ~4 and a chilled steel roll 26. Chilled roll 26, which may be maintained at temperatures ra~ging from 45F to 90F, is advantageously employed to accelerate the cooling of the composite material. The finished composite material 10 is then passed ~rom the line for storage prior to use.

FIG. 2 illustrates in perspective view a sheet of the finished composite material 10 and FIG. 3 is a~ actual photomicrograph of an embodiment of the composite material of this invention, take~ through a cross section of the material such as line 3-3 i~ FIG. 2. As is clear from these fiqures, the fabric 12 forms an outer layer and the film 18 forms an inner layer (these being so referred to so as to denote the positions of the layers when vacuum thermo~orming about an article). In the embodiment illustrated, it can be seen that essentially the entire thickness of the composite material comprising fabric 12 is impregnated with film 18 (i.e., the dimension i, the thickness of the impregnated portion, is only slightl~
smaller than the dimension p, the thickness of the composite). Further, it will be noted that as a result of such impregnation, the film e~tends essentially throughout the entire thic~ness of the composite material. On the C~IC-758 ., . ~ , ;
, other hand, the fabric does not ex~end throllqhollt. the thickness of t~.e fi m and henoe the surface of 'he .r.ner layer is essentia;ly free of fibers. While this particular embodiment is only illustrative and it will be clearly understood that many other variations are possible, ad~antages flow from this particular relationship of inner and outer layers. Specifically, the composite material presents surfaces which have all the attributes of polymer film prior to use in the vacuum thermoforming process. As such, the composite material remains clean and unwrinkled prior to use, is strong and not subject to tearing, linting or stretching, and can easily be rolled and unrolled owing to the relatively low frictional characteristics of the polymer film. As ~ill be seen, however, after use in a thermoforming process, the outer surface will still manifest the desired fabric-like appearance.

Referring now to FIG. 5, illustrated therein is a partial, longitudinal, cross-sectional view of a step in the process of vacuum thermoforming the composite material 10 of this invention about a body which is e~emplified in FIG. 5 by a portion of the insulation body 28 of an automobile hood liner. Body 28, is a preformed body having e~emplary protrusions 30 and depressions 32 as a result of being formed to conform to the inside of the hood of an automobile. Typically, such a body is made of sound and heat insulating material such as bonded glass fibers and is relatively brittle, rigid, and rough-surfaced. As taught herein, this material is to be encapsulated with the composite material of this invention dild vacuum formed about hood liner 28 so as to present a fabric-like aesthetically pleasing outer surface while protecting the body from fiber breakage.

--ll--Accordingly, as is illustrated in FIG. 5, the composite material is laid over and under th~ bo~y 2.t~ with the fabric rich outer layer 12 facing outwardly from the body 28 surfaces and the ilm rich inner layer 18 facing toward the body 28 surfaces. Preferably, the composite material extends beyond the peripheral portion of the body 28 and such e~tensions 37 are sealed together by means of a heated seal bar 38 to totally envelop the body 28 in the composite material 10.
Vacuum probes 34 extend into the body 28, through the composite material 10 and are in flow communication with vacuum manifold 36. Means, not shown, are provided for inducing a vacuum through vacuum manifold 36 and vacuum probes 34 so that the pressure within the confines of the composite material enveloped body 28 is lower than the pressure outside such confines. Such means may comprise a vacuum fan or pump such-as are well known in the art.
Preferably, the lower pressure enclosed within the enveloped body is about 15 inches of mercury vacuum or greater. Means, also not shown, are provided or maintaining the enveloped body at an elevated temperature, e.g. at about 325F to about 425F and, more preferably, from about 350F to about 375F. The specific selection of temperature is such that, in accordance with the teaching herein, the thermoplastic polymer of the inner layer 18 may be softened and adhered to the surface of the body 28 and the portion of the polymer impregnating the outer layer 12 may be drawn away from the outer surface of layer 12. Means for maintaining such temperature may comprise a heated oven in which the vacuum thermoforming process takes place o, other means known to those skilled in the art.

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Referring now to Fi~o 6~ illustrated therein is the same envel~Qed body 28 of ~T~, 5, ~fter heat and Yacu~m h~e been induced. By virtue of such heat and vacuum, composite material 10 has been drawn into conta-t and conformance with the surfaces of the body 28 and the e~tensions 37 have been drawn together and adhered to form a tiqhtly encapsulated finished hood liner, having a sealed peripheral flange comprised of e~tensions 37. The thermoplastic polymer of inner layer 18 is now adhered firmly to the body 28 and portions of the polymer impregnating outer layer 12 have been drawn toward the inner layer 18 so as to expose the fabric-like surface of outer layer 12. This is best illustrated by reference to FIG. 4 which is a photomicrograph of th~ same composite material 10 illustrated in FIG. 3 but shown after the composite material 10 has been subjected to a thermoforming process as has been described above. As is clear from this FIG. 3, ~he polymeric material impregnating outer layer 12 has been drawn away from the surface of outer layer 12, thus e~posing the fabric-like surface.

E~amPles A series of materials are made for comparati~e and e~emplary purposes. In the following description taken in conjunction with the table below, these materials are described in terms of the fabric parameters, film parameters, the process parameters for making them.

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Additionally, the results obtained when using these ~aterials in a ~a~ 7~ th~rmoforming process is cet 13Ut in the table and described below. In the above table it should be noted that FORTREL is a trademark of Fiber Industries Inc. for polyester fibers and TREVIRA is a trademark of Hoechst Celanese Corporation for polyester fibers. The fiber tenacity and the fiber elongation are determined by the method of ASTM D 2101-90. The fabric thickness is determined by ASTM D 1777-64 using a 2 ounce weight on a 1 1/8 inch diameter foot. The film thickness is determined by ASTM D 1777-64 using a 1 ounce weight on a 1/1/8 inch diameter foot. In the process parameter column, the term "entangling snergy~, in horsepower hours per foot, is that employed in the above referenced hydroentangling process of U.S. Patent No. 3,485,706, incorporated herein by reference. All fabrics are made by forming a stabilized web according to the teachings of the U.S. Patent No. 3,485,706 using as a forming member a 103 by 78 polyester monofilament belt in a 3-shed weav~
pattern wherein the warp filaments are 0.15 mm in diameter and the shute filaments are 0.020 mm in diameter. The belt has an open area of 15.1% and was supplied by Appleton Wire Works of Appleton, Wisconsin. The stabilized web was then further stabilized with an acrylic late~ binder at a finished fabric aldon of 10.2% by weight of the binder free web.

The Taber abrasions reerred to in the table are determined by ASTM D 38fl4-80, using a Tabor model 503 abrasor from the Teledyne Taber Company of North Tonawanda, New York and employing CS-O rubber wheels with a 1,000 gram load thereon. The Spencer impact referred to is determined by ASTM D 3420-85. The Mullen burst is determined by TAPPI T403 m-B5.

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The vacuum formability is the subiecti~ ohservatioa of the mater ~l ~n que~ion after suhjec~e ~ 'a ~ vacu~
thermoforming process such as is described herein operating at a temperature of 335F and a vacuum of 22 inches of mercury. Generally, satisfactory formability (designated as ~S~ in the table) is when the resultant encapsulating material conforms to the encapsulated body and maintains such position. Unsatisfactory formability (designated as ~U~ in the table) is when the product separates or when the material separates or fails to conform in whole or in part to the body or forms bubbles or blisters. Heat sealability refers to the ability in the material to seal to itself under the influence of heat and pressure such as the sealing bar referred to in Figure 6. Aesthetics refers to the appearance and feel of the finished vacuum formed encapsulated body wherein aesthetically pleasing fabric-like surfaces which do not lint or form particles is preferable.

In considering the comparative examples 1-4 of the above table, Exampl~ 1 illustrates the use of a fabric alone and while it is clear that such material is unusable for the purposes of vacuum thermoforming, the data is pro~ided to illustrate the Taber Abras;on values which are estremely low. Esample 2 illustrates the use of an all thermoplastic film material and, as e~pected, heat sealability and vacuum formability are e~cellent but the aesthetic properties are certainly unsatisfactory based on the above-described criteria. It should be noted that the Taber a~rasion is substantially higher than for the fabric of Example l.

E~ample 3 is provided to describe a composite material which contrary to the teachings of this invention does not provide for significant impregnating polymer. Instead, 5~

this material has been made by laminatina a pr~form~A ~ lm onto a fabric and passin~ 'hat combin~~ mat~ri~l thr3~gh the nip formed between a resilient and a heated roll at nip pressures of only 6 pounds per linear inch and at temperatures of 325F. The result is a laminated product with insufficient polymer penetration. As can be seen from this Example, the combined materials exhibit a substantially higher Taber abrasion then either of the film or fabric alone. In considering vacuum formability, however, many portions of the encapsulated body remained unadhered to this fabric and instead bubbles and other failure to conform were noted. With respect to aesthetics it was ~ound that the material tended to delaminate; both the film from the fabric and the composite from the encapsulated body.

Esample 4 illustrates a composite material whersin the fabric comprises a substantially high proportion of nonthermoplastic fibers, i.e., rayon fibers. This material produ~ed unsatisfactory vacuum formability in that it failed to conform to the enveloped body.
Accordingly, it is preferred that the fabric consist essentially of thermoplastic fiber and that only that quality of nonthermoplastic fiber which still allow for conformability be included. Most preferably, the fabric is all thermoplastic fiber, and less preferably, contains no more than fi~ty percent t50%) nonthermoplastic fibers.
Examples 5, 6, 7 and 8 all illustrate the production and performance of composite materials made in accordance with the teachings of this invention. Example 5 represents the use of material wherein the percent elongation of fibers is relatively low whereas, Example 6 illustrates a relatively high percent elongation. Example 6 illustrates the use of a particularly thick film as contrasted with the other examples which use a relatively thinner film.

E~ample 7 emploYs fibers of essentially intermediate fiber elon~ation and ~mple ~ i~lustrates fi;~ers ^b~.ained fror, another source and is in other respects similar to that of E~ample 5. In all cases it will be ncted that the vacuum formability was completely satisfactory with good performance and good adherence to the encapsulated body.
Heat sealability was entirely satisfactory and aesthetics were likewise totally satisfactory. It should be noted that the use of the thicker film resulted in substantially higher Taber abrasion values and in all cases the Spencer impact value was greatly increased.

Claims

1. A composite material for use in a vacuum thermoforming process comprising:

an outer layer of nonwoven fabric consisting essentially of thermoplastic fibers capable of elongation upon the application of heat and tensile force; and an inner layer of thermoplastic film; a portion of said film impregnating the fabric and a portion of said film not impregnating the fabric; said film being impregnated into the fabric at an interface between the layers to the degree that the combined thickness of the nonimpregnating portion of the film and the impregnated portion of the fabric is greater than the thickness of the portion of the fabric not impregnated with said film;

whereby, when said composite material is subjected to a thermoforming process, the impregnating film will be drawn toward the inner layer, exposing fibers of the outer layer.

2. The composite material of Claim 1 wherein the fibers have a length of from 19 to about 50 millimeters.

3. The composite material of Claim 1 wherein the fibers have a denier of from about 1 to about 6.

4. The composite material of Claim 1 wherein said fibers have an elongation of at least 20%.

5. The composite material of Claim 1 wherein said fabric has a weight of about 0.5 to about 2 ounces per square yard.

6. The composite material of Claim 1 wherein the fabric has a thickness of from about 10 to about 20 mils.

7. The composite material of Claim 1 wherein the thermoplastic film has a melt temperature of from about 230°F to about 425°F.

8. The composite material of Claim 1 wherein the film has a minimum seal temperature of from about 250°F to about 375°F.

9. The composite material of Claim 1 wherein the film has a thickness of about 3 to about 9 mils.

10. The composite material of Claim 1 wherein said fabric comprises fibers of polyester and said film comprises polyethylene polymer.

11. A method of making a composite material for use in a vacuum thermoforming process comprising:

providing an outer layer of nonwoven fabric consisting essentially of thermoplastic fibers capable of elongation upon the application of heat and tensile force;

providing an inner layer of film comprising thermoplastic polymer in face-to-face relationship with said outer layer;

subjecting said layers to heat and pressure to impregnate a portion of said polymer into the fabric while leaving the remaining portion nonimpregnating;

said polymer being impregnated into the fabric at the interface between the layers to the degree that the combined thickness of the nonimpregnating portion of the film and the impregnated portion of the fabric is greater then the thickness of the portion of the fabric not impregnated;

whereby, when said composite material is subjected to a thermoforming process, the impregnating polymer will be drawn toward the inner layer exposing fibers of the outer layer.

12. The method of Claim 11 wherein said film is extruded onto said fabric prior to the impregnation step.

13. The method of Claim 12 wherein the fabric is preheated prior to the impregnation step.

14. The method of Claim 11 wherein the impregnation step is carried out by passing the film in face-to-face relationship with the fabric through the nip of two rolls at least one of which is heated.

15. The method of Claim 14 wherein said heated roll is heated to a temperature of about 190°F to 205°F.

16. The method of Claim 15 wherein said heated roll is heated to a temperature of about 190°F to about 205°F and the second roll is maintained at a temperature of about 65°F to about 75°F.

17. The method of Claim 14 wherein the nip pressure applied is from about 30 to about 40 pounds per linear inch.

18. The method of Claim 14 wherein said composite material moves at a line speed of about 30 to about 300 feet per minute through said nip.

19. The method of Claim 16 wherein the material leaving the impregnation step passes through the nip formed between said other roll and a chilled roll.

20. The method of Claim 19 wherein the chilled roll is maintained at a temperature of from about 45°F to about 90°F.

21. A method for forming an encapsulated body comprising:

providing a composite material comprising an outer layer of nonwoven fabric consisting essentially of thermoplastic fibers capable of elongation upon the application of heat and tensile force and an inner layer of thermoplastic film, a portion of said film impregnating the fabric and a portion of said film not impregnating the fabric, said film being impregnated into the fabric at an interface between the layers to the degree that the combined thickness of the nonimpregnating portion of the film and the impregnated portion of the fabric is greater than the thickness of the portion of the fabric not impregnated with said film;

enveloping said body in said composite material with said inner layer facing said enveloped body and said outer layer facing outward of said enveloped body;

applying heat and inducing a lower pressure within said enveloped body then without said enveloped body to draw said composite into close contact and conformance with said body and to adhere said thermoplastic polymer to said body while also drawing a portion of said impregnating polymer toward said body thereby exposing impregnated fibers in said outer layer.

22. The method of Claim 21 wherein the temperature at which heat is applied is from about 325°F to about 425°F.

23. The method of Claim 22 wherein the heat is applied at a temperature of about 350°F to about 375°F.

24. The method of Claim 21 wherein the lower pressure induced within the enveloped body is greater than 15 inches of mercury vacuum.

25. The method of Claim 21 wherein the encapsulated body is maintained under the heated and induced lower pressure state for a period of at least from about 4 to about 14 seconds.